reCAPTCHA: Helping the World One Word at a Time
If you're new here, you may want to subscribe to my RSS feed. Thanks for visiting!
While I was looking for a spam filter to block off the large number of spam comments every day, I came across this free Wordpress plugin – reCAPTCHA
reCAPTCHA works just like any other CAPTCHA filter. Readers have to type in the distorted word shown in the generated image before they can have their comments submitted. Since computer program cannot read distorted text as well as a human, a CAPTCHA filter can prevent abuse from “bots”, or automated programs that are written to generate spam.
Helping the World while giving comments
The difference between reCAPTCHA and a normal CAPTCHA filter is that the distorted words generated are taken from old books that were scanned but not recognized by the OCR properly.
These old books are written before computer age. To archive human knowledge and to make information more accessible to the world, these books are being photographically scanned, and then transformed into text using Optical Character Recognition” (OCR). The transformation into text is useful because scanning a book produces images, which are difficult to store on small devices, expensive to download, and cannot be searched. The problem is that OCR is not perfect.
What reCAPTCHA does is to send words that cannot be read by OCR to the Web in the form of CAPTCHA for humans to decipher. What you see below at the comment form is an instant of the reCAPTCHA at work. When you type words from the generated image, you are actually helping to decipher the words that are not recognised by the OCR.
It also comes with an audio challenge that allows blind people to freely navigate your site.
Try it out and have fun!
reCAPTCHA Wordpress plugin: http://recaptcha.net/plugins/wordpress/
reCAPTCHA home page: http://recaptcha.net
